CYCLIZATION OF POLYENES IX ASYMMETRIC CYCLIZATION OF OPTICALLY ACTIVE ESTERS
نویسندگان
چکیده
منابع مشابه
Asymmetric oxidative cation/olefin cyclization of polyenes: evidence for reversible cascade cyclization.
The biosynthesis of cyclic terpenes from polyene precursors by cyclase enzymes is one of nature’s most elegant chemical transformations.[1] The ease with which nature creates complex molecular architectures from achiral precursors has motivated efforts to develop similarly powerful synthetic methodologies.[2] Alimited number of asymmetric methods have been developed,[3] including the notable Br...
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The combination of the N-based pincer ligand PyBOX with Pt2+ leads to new catalysts for the enantioselective cycloisomerization of dienyl- and trienyl-ols. The mechanistic combination of electrophilic cyclization followed by rapid protodemetalation is surprising and leads to a powerful construct for developing new reactions.
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Intramolecular cyclization of nitrogen-tethered alkynyl esters catalyzed by phosphazene organosuperbases P2-tBu and P4-tBu was investigated. Both acyclic and cyclic substrates underwent 5-exo-dig and 5-endo-dig cyclization. This reaction is a rare example of the intramolecular addition of enolates of simple esters to alkynes.
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ژورنال
عنوان ژورنال: Chemistry Letters
سال: 1973
ISSN: 0366-7022,1348-0715
DOI: 10.1246/cl.1973.633